A running test device that evaluates the running characteristic of a rolling element, a tire or a vehicle, by using a metal belt is known. The running test device includes a driven drum and a driving drum, and an endless belt is laid between the driven drum and the driving drum. In the running test device, an upper flat surface of the belt serves as a test road surface. By running the belt while the rolling element is in contact with the test road surface, the running characteristic of the rolling body is evaluated.
While the driven drum and the driving drum are formed to have a truly round cross section, these drums are microscopically not truly round. Moreover, it is difficult to arrange two drums in strictly parallel, and the belt has fine irregularities. For this reason, the belt laid between the two drums meanders or deviates inevitably.
Accordingly, for example, Patent Documents 1 to 3 disclose devices that detect the position of an end of a belt and that correct meandering by tilting a driven drum or adjusting the tension on the basis of the detected belt position.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2004-359379
[Patent Document 2] Japanese Unexamined Patent Application Publication No. 2005-351302
[Patent Document 3] Japanese Unexamined Patent Application Publication No. 2005-326638